Regulator for current generator with cycling reduction means



July 16, 1968 R. SALOMON 3,393,358

REGULATOR FOR CURRENT GENERATOR WITH CYCLING REDUCTION MEANS Filed July 23, 1965 R s 5' (ohm 0 1 Iuvuu'rok .JE;. J.

United S tes Pa e )0.

3 Claims. (61. 322-28) REGULATOR FOR ABSTRACT OF THE DISCLOSURE The present invention generally appertains to improvements in shunt generator regulators and more particularly relates to novel improvements in a two-stage current regulator for a generator; 1

When a conventional two-stage regulator isadjusted for an output of zero or negative, that is, when the'regulated voltage of the second stage is practically the same as the first stage or less than the first stage, a cycling phenomena of the reed between the stages occurs.

This phenomena consists of a disorderly or random movement of the reed, between the two stages, with the cont-acts on the reed successively touching the contacts of the first and second stages. This vibration between the two stages is sufficient to produce a modulation of the current flow, which can be read on the ampmeter scale when the generator is mounted on an automotive vehicle.

The object of the present invention is to provide a circuit arrangement which will obviate the foregoing defects and disadvantages in conventional regulators of this type.

Such object is accomplished by providing a two-stage or multi-stage regulator wherein the movable reed, carrying contacts engageable with contacts in the first and second stages, is influenced by the magnetic attraction of a coil having means associated therewith to maintain one of the reed contacts in engagement with or in close proximity to the contact of the second stage against the force of a resilient means which tends to move the other of the reed contacts into engagement with the contact of the first stage.

Therefore, instead of the random or disorderly cycling action of the reed between the contacts of the first and the second stages, the one contact of the reed is maintained in close proximity to the contact of the second stage and there is a reduction of the amplitude of the vibratory movements of the reed between the contacts of the two stages with the coil retarding the movement of the reed toward the first stage.

Conventionally, the negative output terminal of the coil is directly connected to ground through a resistance element.

In accordance with the present invention, the coil has means associated therewith which generate, at a given time and instantaneously, either a sudden change of voltage at the coil terminals or a sudden change of ampere turns of the coil.

The present invention is described in the following description and illustrated in the accompanying drawings, in which:

FIG. 1 is a circuit diagram of a current regulator in accordance with the present invention, and

FIG. 2 is a circuit diagram of a modified embodiment 3,393,358 Patented July 16, 1968 which attains the same result as the arrangement of FIG. 1

Referring first-to FIG. 1, the regulator Rg, shown in its entirety in the block, comprises a vibratory reed 1 having an end provided with contacts 3a and 4a positioned in back to back relation on the end. The movable reedis connected in series between the positive pole 12 of the battery B and the inductor coil 5 of the generator G.

The first'stage'includes a line that bridges the contact 3b and connects the terminal 12 to the coil 5 through a variable resistor 2. The movable reed 1 is capable of shorting out the variable resistor 2 of the first stage through engagement of reed contact 3a with the fixed contact 3b of the first stage, or the inductor coil 5 by engagement of the reed contact 4a with the fixed contact 7 4b of the second stage.

The reed is connected to the armature A associated with the magnetic coil 7 so as to move the reed contact 4a toward the contact 4b, and the reed is subjected to the return forceof a spring S which tends to pull the reed contact 3a into engagement with the contact 3b.

One end of the coil 7 is connected through the terminal 9 to the generator output conductor to supply to such terminal a variable source of current responsive to running speeds of the generator. The other end of the coil 7 is connected at junction 10 to the negative contact 4b of the second stage and to one end of a resistor 6 whose other end is tied to ground.

Initially, a trickle current flows from source 12, through the variable resistor 2, to the inductor coil 5 to overcome initial inductive resistance, the reed being in a neutral position with its contacts out of engagement with the contacts of either the first or the second stages.

In operation, before the contacts 4a and 4b are closed, the resistor 6 carries current 1 from terminal 9, and the voltage drop across this resistor is V At the same time current I is flowing through the resistor 2 and the coil 5, and the control voltage at terminal 9 is at a value V As the generator speed is increased the value of current I increases until it is sufficient to close the contacts 4a and 4b. Just prior to closing contacts 4a and 4b the voltage drop V across resistor 2 is equal to 1 R where R is the value of resistor 6.

When contacts 4a and 4b are closed, the resistor 6 carries additional current I from terminal 12 through the variable resistor 2 and contacts 4a and 417 so that the voltage drop V across resistor 6 now becomes equal to (I -|-I )R. By inspection, V is greater than V When the contacts 4a and 4b are closed, the current flow in coil 5 is decreased, thereby decreasing the output of the generator which, in turn, results in a reduction of the system control voltage at terminal 9' to a value V V V As soon as the system voltage applied to terminal 9 is decreased to a value V the movable reed is caused by the spring force to start to move toward contact 3b of the first stage, the contacts 4a and 4b opening.

At this instant, the coil 7 which was supplied by voltage V V is subjected to voltage V V V V Therefore, the coil 7 now exerts a stronger attraction on the movable reed and the movement of the reed toward contact 3b under the force of the resilient means S, is retarded, thereby decreasing the amplitude of the cycling and causing the contact 4a to stay in proximity to or in engagement with the contact 4b.

In the second form, as shown in FIG. 2 (wherein elements similar in construction and operation to those shown in FIG. 1 are given the same reference numerals which are primed), the sudden pulling force applied to the movable reed 1', when contacts 4a and 4b open, instead of being retarded by the sudden change of voltage at the terminals of coil 7, is retarded by a sudden change of the ampere turns of control.

For this purpose, in addition to the coil 7, an auxiliary coil 11 is employed, with or without a flow of current I when contacts 4a and 4b are either closed .or opened. The ampere turns in the auxiliary coil 11 are in opposition with the ampere turns in the coil 7, so that the coil 11 bucks the coil 7.

At the movement when the contacts 4a and 4b open, current 1 no longer passes through coil 11 and the total control current of coil 7', or, otherwise stated, the ampere turns of control in coil 7 results in N I N I substan: tially equal to N 1 This retards the movement of the reed toward the contact 3b of the first stage.

While the best known forms of the present invention have been shown and described herein, modification may be made in the circuits within the spirit and scope of the appended claims.

What is claimed is:

1. In combination with a generator having terminals and a field circuit including a field winding and a field resistance, a voltage regulator comprising a magnet having a vibratory armature responsive to energization of said magnet, said magnet having an energizing coil, and the regulator including a pair of contacts adapted to be electrically connected with said armature by vibration of said armature, circuit connections connecting said winding at one end to one of said terminals and at its other 4 end to said armature, circuit connections connecting the other of said terminals to one of said contacts and one end of said energizing coil, said energizing coilbeing connected between said terminals, said field resistance being connected across said armature and said one contact, the improvement comprising:

a circuit element connected between the other of said pair of contacts and said one terminal for sharply reducing the efiect of said. energizing coil on said armature when the armature is in electrical contact with said other contact.

2. The combination as defined in claim 1 wherein said circuit element is a resistance connecting said energizing coil to said other contact.

3. The combination as defined in claim 1 wherein said circuit element is an auxiliary coil wound to oppose said energizing coil.

References Cited UNITED STATES PATENTS 2,052,048 8/ 1936' Leece 32284 X 2,052,049 8/1936 Leece 322-84 X 2,520,689 8/1950 Niemi 322--84 X FOREIGN PATENTS 672,307 3/ 1939 Germany.

'ORIS L. RADER, Primary Examiner.

H. HUBERFELD, Assistant Examiner. 

